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7.2: Panua na Gawanya Maneno ya busara

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    176752
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    Malengo ya kujifunza

    Mwishoni mwa sehemu hii, utaweza:

    • Kuamua maadili ambayo kujieleza kwa busara haijulikani
    • Kurahisisha maneno ya busara
    • Kuzidisha maneno ya busara
    • Gawanya maneno ya busara
    • Panua na ugawanye kazi za busara

    Kabla ya kuanza, fanya jaribio hili la utayari.

    1. Kurahisisha:\(\dfrac{90y}{15y^2}\).
      Ikiwa umekosa tatizo hili, tathmini [kiungo].
    2. Kuzidisha:\(\dfrac{14}{15}·\dfrac{6}{35}\).
      Ikiwa umekosa tatizo hili, tathmini [kiungo].
    3. Gawanya:\(\dfrac{12}{10}÷\dfrac{8}{25}\).
      Ikiwa umekosa tatizo hili, tathmini [kiungo].

    Tulipitia upya mali ya sehemu ndogo na shughuli zao. Tulianzisha namba za busara, ambazo ni sehemu ndogo tu ambapo nambari na denominators ni integers. Katika sura hii, tutafanya kazi na sehemu ambazo nambari na denominators ni polynomials. Tunaita aina hii ya kujieleza kuwa kujieleza kwa busara.

    MANENO YA BUSARA

    Maneno ya busara ni usemi wa fomu\(\dfrac{p}{q}\), where \(p\) na\(q\) ni polynomials na\(q\neq 0\).

    Hapa ni baadhi ya mifano ya maneno ya busara:

    \[−\dfrac{24}{56} \qquad \dfrac{5x}{12y} \qquad \dfrac{4x+1}{x^2−9} \qquad \dfrac{4x^2+3x−1}{2x−8}\nonumber\]

    Kumbuka kwamba kwanza busara kujieleza waliotajwa hapo juu\(−\dfrac{24}{56}\),, ni sehemu tu. Kwa kuwa mara kwa mara ni polynomial na sifuri shahada, uwiano wa constants mbili ni kujieleza busara, mradi denominator si sifuri.

    Tutafanya shughuli sawa na maneno ya busara ambayo tulifanya kwa sehemu ndogo. Sisi kurahisisha, kuongeza, Ondoa, kuzidisha, kugawanya na kuitumia katika programu.

    Tambua Maadili ambayo Ufafanuzi wa busara haukufafanuliwa

    Ikiwa denominator ni sifuri, kujieleza kwa busara haijulikani. Nambari ya kujieleza kwa busara inaweza kuwa 0—lakini sio denominator.

    Tunapofanya kazi na sehemu ya namba, ni rahisi kuepuka kugawa kwa sifuri kwa sababu tunaweza kuona namba katika denominator. Ili kuepuka kugawa kwa sifuri kwa kujieleza kwa busara, hatupaswi kuruhusu maadili ya kutofautiana ambayo itafanya denominator kuwa sifuri.

    Hivyo kabla ya kuanza operesheni yoyote na kujieleza mantiki, sisi kuchunguza ni kwanza kupata maadili ambayo kufanya denominator sifuri. Kwa njia hiyo, tunapotatua usawa wa busara kwa mfano, tutajua kama ufumbuzi wa algebraic tunayopata unaruhusiwa au la.

    KUAMUA MAADILI AMBAYO MANENO YA BUSARA HAIJULIKANI.
    1. Weka denominator sawa na sifuri.
    2. Kutatua equation.
    MFANO\(\PageIndex{1}\)

    Tambua thamani ambayo kila kujieleza kwa busara haijulikani:

    a.\(\dfrac{8a^2b}{3c}\) b.\(\dfrac{4b−3}{2b+5}\) c\(\dfrac{x+4}{x^2+5x+6}\).

    Suluhisho

    Maneno hayatakuwa na ufafanuzi wakati denominator ni sifuri.

    a.

    \(\begin{array} {ll} &\dfrac{8a^2b}{3c} \\ \begin{array} {l} \text{Set the denominator equal to zero and solve} \\ \text{for the variable.} \end{array} &3c=0 \\ &c=0 \\ &\dfrac{8a^2b}{3c}\text{ is undefined for }c=0 \end{array} \)
    b.

    \(\begin{array} {ll} &\dfrac{4b-3}{2b+5} \\ \begin{array} {l} \text{Set the denominator equal to zero and solve} \\ \text{for the variable.} \end{array} &2b+5=0 \\ &2b=-5 \\ &b=-\dfrac{5}{2} \\ & \\ &\dfrac{4b-3}{2b+5} \text{ is undefined for }b=-\dfrac{5}{2} \end{array} \)

    c.

    \(\begin{array} {ll} &\dfrac{x+4}{x^2 + 5x + 6} \\ \begin{array} {l} \text{Set the denominator equal to zero and solve } \\ \text{for the variable.} \end{array} &x^2+5x+6=0 \\ &(x+2)(x+3)=0 \\ &x+2=0\text{ or }x+3=0 \\ &x=-2\text{ or }x=-3 \\ & \\ &\dfrac{x+4}{x^2+5x+6}\text{ is undefined for }x=-2\text{ or }x=-3 \end{array} \)

    Jaribu\(\PageIndex{2}\)

    Tambua thamani ambayo kila kujieleza kwa busara haijulikani.

    a.\(\dfrac{3y^2}{8x}\) b.\(\dfrac{8n−5}{3n+1}\) c.\(\dfrac{a+10}{a^2+4a+3}\)

    Jibu

    a.\(x=0\)
    b.\(n=−\dfrac{1}{3}\)
    c.\(a=−1,a=−3\)

    Jaribu\(\PageIndex{3}\)

    Tambua thamani ambayo kila kujieleza kwa busara haijulikani.

    a.\(\dfrac{4p}{5q}\) b.\(\dfrac{y−1}{3y+2}\) c.\(\dfrac{m−5}{m^2+m−6}\)

    Jibu

    a.\(q=0\)
    b.\(y=−\dfrac{2}{3}\)
    c.\(m=2,m=−3\)

    Kurahisisha maneno ya busara

    Sehemu inachukuliwa kuwa rahisi ikiwa hakuna mambo ya kawaida, isipokuwa 1, katika nambari yake na denominator. Vile vile, kujieleza rahisi kwa busara hauna mambo ya kawaida, isipokuwa 1, katika nambari yake na denominator.

    RAHISI MANENO YA BUSARA

    Maneno ya busara yanachukuliwa kuwa rahisi ikiwa hakuna mambo ya kawaida katika nambari yake na denominator.

    Kwa mfano,

    \[ \begin{array} {l} \dfrac{x+2}{x+3} \text{ is simplified because there are no common factors of } x+2 \text{ and }x+3. \\ \dfrac{2x}{3x} \text{ is not simplified because x is a common factor of }2x\text{ and }3x. \\ \end{array} \nonumber\]

    Tunatumia Mali sawa FRACTIONS ili kurahisisha sehemu ndogo za namba. Tunarudia tena hapa kama tutakayotumia pia ili kurahisisha maneno ya busara.

    SAWA FRACTIONS MALI

    Kama\(a\),\(b\), na\(c\) ni idadi ambapo\(b\neq 0,c\neq 0,\)

    \[\text {then } \dfrac{a}{b}=\dfrac{a·c}{b·c} \text{ and } \dfrac{a·c}{b·c}=\dfrac{a}{b}\nonumber\]

    Ona kwamba katika Mali sawa Fractions, maadili ambayo ingeweza kufanya denominators sifuri ni hasa haruhusiwi. Tunaona\(b\neq 0,c\neq 0\) wazi.

    Ili kurahisisha maneno ya busara, sisi kwanza tunaandika nambari na denominator katika fomu iliyopangwa. Kisha sisi kuondoa mambo ya kawaida kwa kutumia sawa Fractions Mali.

    Kuwa makini sana kama wewe kuondoa mambo ya kawaida. Mambo yanaongezeka ili kufanya bidhaa. Unaweza kuondoa sababu kutoka kwa bidhaa. Huwezi kuondoa muda kutoka kwa jumla.

    Maneno ya busara ni wingi mara 2 mara 3 7 iliyogawanywa na wingi mara 3 mara 5 7 ni 3 na 7. Sababu zake za kawaida ni 3 na 7, ambazo ni sababu za bidhaa. Wakati wao ni kuondolewa, matokeo ni mbili-tano. Maneno ya busara ni bidhaa ya 3 x na wingi x minus 9 imegawanywa na bidhaa ya 5 na kiasi x chini ya 9. Sababu ya kawaida ni x minus 9, ambayo ni sababu ya bidhaa. Unapoondolewa, matokeo ni 3 x imegawanywa na 5. Maneno ya busara ni wingi x pamoja na 5 iliyogawanywa na 5. Kuna x wote nambari na denomiantor. Hata hivyo, ni neno la jumla katika nambari. Maneno ya busara hayana mambo ya kawaida.

    Kuondoa ya\(x\) kutoka\(\dfrac{x+5}{x}\) itakuwa kama kufuta katika sehemu\(2\)\(\dfrac{2+5}{2}!\)

    Jinsi ya kurahisisha kujieleza kwa busara

    MFANO\(\PageIndex{4}\)

    Kurahisisha:\(\dfrac{x^2+5x+6}{x^2+8x+12}\)

    Suluhisho

    Hatua ya 1 ni kuzingatia nambari na denominator kabisa katika kujieleza kwa busara, kiasi x mraba pamoja 5 x pamoja na sita kugawanywa na wingi x mraba 8 x pamoja 12. Nambari, x mraba pamoja na 5 x pamoja na sita, sababu katika wingi x pamoja na mara 2 kiasi x pamoja 3. Denominator, x mraba 8 x pamoja na 12, sababu katika wingi x pamoja na mara 2 kiasi x pamoja 6.Hatua ya 2 ni kurahisisha kujieleza kwa busara, kiasi x pamoja na mara 2 kiasi x pamoja na 3 yote imegawanywa na wingi x pamoja na mara 2 kiasi x plus 6, kwa kugawanya sababu ya kawaida, x pamoja na 6. Matokeo ya kuondoa jambo la kawaida ni wingi x pamoja na 3 umegawanyika na wingi x plus 6, ambapo x si sawa na 2 na x si sawa na -6.

    Jaribu\(\PageIndex{5}\)

    Kurahisisha:\(\dfrac{x^2−x−2}{x^2−3x+2}\).

    Jibu

    \(\dfrac{x+1}{x−1},x\neq 2,x\neq 1\)

    Jaribu\(\PageIndex{6}\)

    Kurahisisha:\(\dfrac{x^2−3x−10}{x^2+x−2}\).

    Jibu

    \(\dfrac{x−5}{x−1},x\neq −2,x\neq 1\)

    Sasa tunafupisha hatua unazopaswa kufuata ili kurahisisha maneno ya busara.

    KURAHISISHA MANENO YA BUSARA.
    1. Fanya namba na denominator kabisa.
    2. Kurahisisha kwa kugawa mambo ya kawaida.

    Kawaida, tunaacha maneno rahisi ya busara katika fomu iliyopangwa. Kwa njia hii, ni rahisi kuangalia kwamba tumeondoa mambo yote ya kawaida.

    Tutatumia mbinu tumejifunza kwa sababu ya polynomials katika numerators na denominators katika mifano ifuatayo.

    Kila wakati sisi kuandika kujieleza busara, tunapaswa kutoa taarifa disallowing maadili ambayo kufanya denominator sifuri. Hata hivyo, ili tuangalie kazi iliyopo, tutaacha kuandika katika mifano.

    MFANO\(\PageIndex{7}\)

    Kurahisisha:\(\dfrac{3a^2−12ab+12b^2}{6a^2−24b^2}\).

    Suluhisho

    \(\begin{array} {ll} &\dfrac{3a^2−12ab+12b^2}{6a^2−24b^2} \\ & \\ & \\ \begin{array} {l} \text{Factor the numerator and denominator,} \\ \text{first factoring out the GCF.} \end{array} &\dfrac{3(a^2−4ab+4b^2)}{6(a^2−4b^2)} \\ & \\ &\dfrac{3(a−2b)(a−2b)}{6(a+2b)(a−2b)} \\ & \\ \text{Remove the common factors of }a−2b\text{ and }3. &\dfrac{\cancel{3}(a−2b)\cancel{(a−2b)}}{\cancel{3}·2(a+2b)\cancel{(a−2b)}} \\ &\dfrac{a−2b}{2(a+2b)} \end{array} \)

    Jaribu\(\PageIndex{8}\)

    Kurahisisha:\(\dfrac{2x^2−12xy+18y^2}{3x^2−27y^2}\).

    Jibu

    \(\dfrac{2(x−3y)}{3(x+3y)}\)

    Jaribu\(\PageIndex{9}\)

    Kurahisisha:\(\dfrac{5x^2−30xy+25y^2}{2x^2−50y^2}\).

    Jibu

    \(\dfrac{5(x−y)}{2(x+5y)}\)

    Sasa tutaona jinsi ya kurahisisha kujieleza kwa busara ambao nambari na denominator zina mambo tofauti. Sisi hapo awali ilianzisha notation kinyume: kinyume cha\(a\) ni\(−a\) na\(−a=−1·a\).

    sehemu ya namba, kusema\(\dfrac{7}{−7}\) simplifies kwa\(−1\). Pia tunatambua kwamba nambari na denominator ni kinyume.

    Sehemu\(\dfrac{a}{−a}\), ambayo nambari yake na denominator ni kinyume pia inaeleza\(−1\).

    \[\begin{array} {ll} \text{Let’s look at the expression }b−a. &b−a \\ \text{Rewrite.} &−a+b \\ \text{Factor out }–1. &−1(a−b) \nonumber\end{array} \]

    Hii inatuambia kwamba\(b−a\) ni kinyume cha\(a−b\).

    Kwa ujumla, tunaweza kuandika kinyume cha\(a−b\) kama\(b−a\). Hivyo kujieleza kwa busara\(\dfrac{a−b}{b−a}\) kurahisisha\(−1\).

    KUPINGA KATIKA KUJIELEZA BUSARA

    Kinyume cha\(a−b\) ni\(b−a\).

    \[\dfrac{a−b}{b−a}=−1 \quad a\neq b\nonumber\]

    Maneno na mgawanyiko wake kinyume na\(−1\).

    Tutatumia mali hii ili kurahisisha maneno ya busara ambayo yana kinyume katika nambari zao na denominators. Kuwa makini si kutibu\(a+b\) na\(b+a\) kama kupinga. Kumbuka kwamba kwa kuongeza, ili haijalishi hivyo\(a+b=b+a\). Hivyo kama\(a\neq −b\), basi\(\dfrac{a+b}{b+a}=1\).

    MFANO\(\PageIndex{10}\)

    Kurahisisha:\(\dfrac{x^2−4x−32}{64−x^2}\)

    Suluhisho

      .
    Fanya namba na denominator. .
    Tambua mambo ambayo yanapinga. .
    Kurahisisha. .
    Jaribu\(\PageIndex{11}\)

    Kurahisisha:\(\dfrac{x^2−4x−5}{25−x^2}\)

    Jibu

    \(−\dfrac{x+1}{x+5}\)

    Jaribu\(\PageIndex{12}\)

    Kurahisisha:\(\dfrac{x^2+x−2}{1−x^2}\).

    Jibu

    \(−\dfrac{x+2}{x+1}\)

    Kuzidisha maneno ya busara

    Ili kuzidisha maneno ya busara, tunafanya tu kile tulichofanya na sehemu ndogo za namba. Sisi kuzidisha nambari na kuzidisha denominators. Kisha, ikiwa kuna mambo yoyote ya kawaida, tunawaondoa ili kurahisisha matokeo.

    KUZIDISHA MANENO YA BUSARA

    Ikiwa\(p\),\(q\),\(r\), na\(s\) ni polynomials ambapo\(q\neq 0\)\(s\neq 0\), basi

    \[\dfrac{p}{q}·\dfrac{r}{s}=\dfrac{pr}{qs}\nonumber\]

    Ili kuzidisha maneno ya busara, kuzidisha nambari na kuzidisha denominators.

    Kumbuka, katika sura hii, tutafikiri kwamba maadili yote ya namba ambayo yangeweza kufanya denominator kuwa sifuri hutolewa. Hatuwezi kuandika vikwazo kwa kila kujieleza kwa busara, lakini kukumbuka kwamba denominator haiwezi kamwe kuwa sifuri. Hivyo katika mfano huu ijayo,\(x\neq 0\),\(x\neq 3\), na\(x\neq 4.\)

    MFANO\(\PageIndex{13}\): How to Multiply Rational Expressions

    Kurahisisha:\(\dfrac{2x}{x^2−7x+12}·\dfrac{x^2−9}{6x^2}\).

    Suluhisho

    Hatua ya 1 ni kuzingatia kila nambari na denominator kabisa katika 2 x imegawanywa na wingi x mraba bala 7 x pamoja na mara 12 kujieleza busara kiasi x squared bala 9 imegawanywa na 6 x mraba. Denominator, x squared minus 7 x pamoja na 12, sababu katika kiasi x minus mara 3 kiasi x minus 4. Nambari x squared minus mambo 9 katika wingi x minus mara 3 kiasi x pamoja 3.Hatua ya 2 ni kuzidisha nambari 2 x na wingi x bala mara 3 kiasi x pamoja 3, na denominators kiasi x bala mara 3 kiasi x minus 4 na 6 x squared. Ni muhimu kuandika monomials katika nambari na katika denominator. kwanza.Hatua ya 3 ni kurahisisha 2 x mara wingi x bala mara 3 wingi x pamoja na 3 wote kugawanywa na mara 2 mara 3 x mara x mara wingi x bala mara 3 kiasi x pamoja 4 kwa kugawa nje sababu ya kawaida, x minus 3. Kuacha denominator kwa fomu iliyopangwa, matokeo ni kiasi x pamoja na 3 kugawanywa na 3 x mara kiasi x minus 4.

    Jaribu\(\PageIndex{14}\)

    Kurahisisha:\(\dfrac{5x}{x^2+5x+6}·\dfrac{x^2−4}{10x}\).

    Jibu

    \(\dfrac{x−2}{2(x+3)}\)

    Jaribu\(\PageIndex{15}\)

    Kurahisisha:\(\dfrac{9x^2}{x^2+11x+30}·\dfrac{x^2−36}{3x^2}\).

    Jibu

    \(\dfrac{3(x−6)}{x+5}\)

    ONGEZA MANENO YA BUSARA.
    1. Factor kila nambari na denominator kabisa.
    2. Kuzidisha nambari na denominators.
    3. Kurahisisha kwa kugawa mambo ya kawaida.
    MFANO\(\PageIndex{16}\)

    Kuzidisha:\(\dfrac{3a^2−8a−3}{a^2−25}·\dfrac{a^2+10a+25}{3a^2−14a−5}\).

    Suluhisho

    \(\begin{array} {ll} &\dfrac{3a^2−8a−3}{a^2−25}·\dfrac{a^2+10a+25}{3a^2−14a−5} \\ & \\ \begin{array} {ll} \text{Factor the numerators and denominators} \\ \text{and then multiply.} \end{array} &\dfrac{(3a+1)(a−3)(a+5)(a+5)}{(a−5)(a+5)(3a+1)(a−5)} \\ & \\ \begin{array} {l} \text{Simplify by dividing out} \\ \text{common factors.} \end{array} &\dfrac{\cancel{(3a+1)}(a−3)\cancel{(a+5)}(a+5)}{(a−5)\cancel{(a+5)}\cancel{(3a+1)}(a−5)} \\ & \\ \text{Simplify.} &\dfrac{(a−3)(a+5)}{(a−5)(a−5)} \\ & \\ \text{Rewrite }(a−5)(a−5)\text{ using an exponent.} &\dfrac{(a−3)(a+5)}{(a−5)^2} \end{array}\)

    Jaribu\(\PageIndex{17}\)

    Kurahisisha:\(\dfrac{2x^2+5x−12}{x^2−16}·\dfrac{x^2−8x+16}{2x^2−13x+15}\).

    Jibu

    \(\dfrac{x−4}{x−5}\)

    Jaribu\(\PageIndex{18}\)

    Kurahisisha:\(\dfrac{4b^2+7b−2}{1−b^2}·\dfrac{b^2−2b+1}{4b^2+15b−4}\).

    Jibu

    \(−\dfrac{(b+2)(b−1)}{(1+b)(b+4)}\)

    Gawanya Maneno ya busara

    Kama tulivyofanya kwa vipande vya namba, kugawanya maneno ya busara, tunazidisha sehemu ya kwanza kwa usawa wa pili.

    IDARA YA MANENO YA BUSARA

    Ikiwa\(p\),\(q\),\(r\), na\(s\) ni polynomials ambapo\(q\neq 0\),\(r\neq 0\),\(s\neq 0\), basi

    \[\dfrac{p}{q}÷\dfrac{r}{s}=\dfrac{p}{q}·\dfrac{s}{r}\nonumber\]

    Ili kugawanya maneno ya busara, kuzidisha sehemu ya kwanza kwa usawa wa pili.

    Mara tu tunapoandika tena mgawanyiko kama kuzidisha kwa kujieleza kwanza kwa usawa wa pili, sisi kisha tunafanya kila kitu na kuangalia mambo ya kawaida.

    MFANO\(\PageIndex{19}\): How to Divide Rational Expressions

    Gawanya:\(\dfrac{p^3+q^3}{2p^2+2pq+2q^2}÷\dfrac{p^2−q^2}{6}\).

    Suluhisho

    Hatua ya 1 ni kuandika tena mgawanyiko wa kujieleza kwa busara, kiasi p cubed pamoja q cubes kugawanywa na wingi 2 p mraba pamoja 2 p q pamoja 2 q mraba kugawanywa na kujieleza busara, wingi p mraba bala q mraba wote umegawanyika na 6. Fanya hili kwa kufuta maneno ya busara, kiasi p squared minus q squared wote kugawanywa na 6, na kubadilisha mgawanyiko kwa kuzidisha. Matokeo yake ni kiasi p cubed pamoja q cubes kugawanywa na wingi 2 p squared pamoja 2 p q pamoja 2 q mara mraba kiasi 6 kugawanywa na wingi p squared bala q squared.Hatua ya 2 ni kuzingatia nambari, kiasi p cubed pamoja q cubed na 6, na denominators, kiasi cha 2 p mraba pamoja 2 p q pamoja na 2 mraba na kiasi p squared bala q mraba, kabisa. Matokeo yake ni wingi p pamoja na q mara wingi p squared minus p q pamoja q squared mara zote kiasi 2 mara 3 kugawanywa na wingi p minus q mara wingi p pamoja q.Hatua ya 3 ni kuzidisha nambari na denominators. Matokeo yake ni wingi p pamoja na q mara wingi p squared minus p q pamoja q mara za mraba mara 2 3 yote imegawanywa na mara 2 kiasi p squared pamoja p q pamoja q mara squared wingi p minus q mara wingi p pamoja q.Hatua ya 4 ni kurahisisha maneno kwa kugawanya mambo ya kawaida, wingi p pamoja q na 2. Matokeo yake ni mara 3 kiasi p squared minus p q pamoja q squared wote kugawanywa na wingi p minus q mara kiasi p squared pamoja p q pamoja q squared.

    Jaribu\(\PageIndex{20}\)

    Kurahisisha:\(\dfrac{x^3−8}{3x^2−6x+12}÷\dfrac{x^2-4}{6}\).

    Jibu

    \(\dfrac{2(x^2+2x+4)}{(x+2)(x^2−2x+4)}\)

    Jaribu\(\PageIndex{21}\)

    Kurahisisha:\(\dfrac{2z^2}{z^2−1}÷\dfrac{z^3−z^2+z}{z^3+1}\).

    Jibu

    \(\dfrac{2z}{z−1}\)

    IDARA YA MANENO YA BUSARA
    1. Andika upya mgawanyiko kama bidhaa ya kujieleza kwa busara ya kwanza na usawa wa pili.
    2. Factor numerators na denominators kabisa.
    3. Kuzidisha nambari na denominators pamoja.
    4. Kurahisisha kwa kugawa mambo ya kawaida.

    Kumbuka kutoka Matumizi Lugha ya Algebra kwamba sehemu tata ni sehemu ambayo ina sehemu katika nambari, denominator au wote wawili. Pia, kumbuka bar sehemu ina maana mgawanyiko. Sehemu ngumu ni njia nyingine ya kuandika mgawanyiko wa sehemu mbili.

    MFANO\(\PageIndex{22}\)

    Gawanya:\(\dfrac{\dfrac{6x^2−7x+2}{4x−8}}{\dfrac{2x^2−7x+3}{x^2−5x+6}}\).

    Suluhisho

    \(\begin{array} {ll} &\dfrac{\dfrac{6x^2−7x+2}{4x−8}}{\dfrac{2x^2−7x+3}{x^2−5x+6}} \\ & \\ \text{Rewrite with a division sign.} &\dfrac{6x^2−7x+2}{4x−8}÷\dfrac{2x^2−7x+3}{x^2−5x+6} \\ & \\ \begin{array} {l} \text{Rewrite as product of first times reciprocal} \\ \text{of second.} \end{array} &\dfrac{6x^2−7x+2}{4x−8}·\dfrac{x^2−5x+6}{2x^2−7x+3} \\ & \\ \begin{array} {l} \text{Factor the numerators and the} \\ \text{denominators, and then multiply.} \end{array} &\dfrac{(2x−1)(3x−2)(x−2)(x−3)}{4(x−2)(2x−1)(x−3)} \\ & \\ \text{Simplify by dividing out common factors.} &\dfrac{\cancel{(2x−1)}(3x−2)\cancel{(x−2)}\cancel{(x−3)}}{4\cancel{(x−2)}\cancel{(2x−1)}\cancel{(x−3)}} \\ \text{Simplify.} &\dfrac{3x−2}{4} \end{array}\)

    Jaribu\(\PageIndex{23}\)

    Kurahisisha:\(\dfrac{\dfrac{3x^2+7x+2}{4x+24}}{\dfrac{3x^2−14x−5}{x^2+x−30}}\).

    Jibu

    \(\dfrac{x+2}{4}\)

    Jaribu\(\PageIndex{24}\)

    Kurahisisha:\(\dfrac{\dfrac{y^2−36}{2y^2+11y−6}}{\dfrac{2y^2−2y−60}{8y−4}}\).

    Jibu

    \(\dfrac{2}{y+5}\)

    Ikiwa tuna maneno zaidi ya mbili ya busara ya kufanya kazi na, bado tunafuata utaratibu huo. Hatua ya kwanza itakuwa kuandika tena mgawanyiko wowote kama kuzidisha kwa usawa. Kisha, tunazingatia na kuzidisha.

    MFANO\(\PageIndex{25}\)

    Fanya shughuli zilizoonyeshwa:\(\dfrac{3x−6}{4x−4}·\dfrac{x^2+2x−3}{x^2−3x−10}÷\dfrac{2x+12}{8x+16}\).

    Suluhisho

      .
    Andika upya mgawanyiko kama kuzidisha
    kwa usawa.
    .
    Factor numerators na denominators. .
    Panua sehemu ndogo. Kuleta mara kwa
    mara mbele itasaidia wakati wa kuondoa mambo ya kawaida.
     
    Kurahisisha kwa kugawa mambo ya kawaida. .
    Kurahisisha. .
    Jaribu\(\PageIndex{26}\)

    Fanya shughuli zilizoonyeshwa:\(\dfrac{4m+4}{3m−15}·\dfrac{m^2−3m−10}{m^2−4m−32}÷\dfrac{12m−36}{6m−48}\).

    Jibu

    \(\dfrac{2(m+1)(m+2)}{3(m+4)(m−3)}\)

    Jaribu\(\PageIndex{27}\)

    Fanya shughuli zilizoonyeshwa:\(\dfrac{2n^2+10n}{n−1}÷\dfrac{n^2+10n+24}{n^2+8n−9}·\dfrac{n+4}{8n^2+12n}\).

    Jibu

    \(\dfrac{(n+5)(n+9)}{2(n+6)(2n+3)}\)

    Kuzidisha na Kugawanya Kazi

    Tulianza sehemu hii na kusema kuwa kujieleza busara ni usemi wa fomu\(\dfrac{p}{q}\), ambapo p na q ni polynomials na\(q\neq 0\). Vile vile, tunafafanua kazi ya busara kama kazi ya fomu\(R(x)=\dfrac{p(x)}{q(x)}\) ambapo\(p(x)\) na\(q(x)\) ni kazi nyingi na\(q(x)\) sio sifuri.

    KAZI YA BUSARA

    Kazi ya busara ni kazi ya fomu

    \[R(x)=\dfrac{p(x)}{q(x)}\nonumber\]

    wapi\(p(x)\) na\(q(x)\) ni kazi polynomial na\(q(x)\) si sifuri.

    Kikoa cha kazi ya busara ni namba zote halisi isipokuwa kwa maadili hayo ambayo yangeweza kusababisha mgawanyiko kwa sifuri. Lazima tuondoe maadili yoyote ambayo hufanya\(q(x)=0\).

    KUAMUA UWANJA WA KAZI YA BUSARA.
    1. Weka denominator sawa na sifuri.
    2. Kutatua equation.
    3. Kikoa ni namba zote halisi ukiondoa maadili yaliyopatikana katika Hatua ya 2.
    MFANO\(\PageIndex{28}\)

    Kupata uwanja wa\(R(x)=\dfrac{2x^2−14x}{4x^2−16x−48}\).

    Suluhisho

    Kikoa kitakuwa namba zote halisi isipokuwa maadili hayo yanayofanya denominator sifuri. Tutaweka denominator sawa na sifuri, kutatua equation hiyo, na kisha uondoe maadili hayo kutoka kwenye kikoa.

    \(\begin{array} {ll} \text{Set the denominator to zero.} &4x^2−16x−48=0 \\ \text{Factor, first factor out the GCF.} &4(x^2−4x−12)=0 \\ &4(x−6)(x+2)=0 \\ \text{Use the Zero Product Property.} &4\neq 0\quad x−6=0\quad x+2=0 \\ \text{Solve.} &\hspace{24mm}x=6\qquad x=−2 \\ &\text{The domain of }R(x)\text{ is all real numbers} \\ &\text{where }x\neq 6\text{ and }x\neq −2 \end{array}\).

    Jaribu\(\PageIndex{29}\)

    Kupata uwanja wa\(R(x)=\dfrac{2x^2−10x}{4x^2−16x−20}\).

    Jibu

    uwanja wa\(R(x)\) ni namba zote halisi ambapo\(x\neq 5\) na\(x\neq −1\).

    Jaribu\(\PageIndex{30}\)

    Kupata uwanja wa\(R(x)=\dfrac{4x^2−16x}{8x^2−16x−64}\).

    Jibu

    uwanja wa\(R(x)\) ni namba zote halisi ambapo\(x\neq 4\) na\(x\neq −2\).

    Ili kuzidisha kazi za busara, tunazidisha maneno ya busara yanayosababisha upande wa kulia wa equation kwa kutumia mbinu sawa ambazo tulizitumia kuzidisha maneno ya busara.

    MFANO\(\PageIndex{31}\)

    Pata\(R(x)=f(x)·g(x)\) wapi\(f(x)=\dfrac{2x−6}{x^2−8x+15}\) na\(g(x)=\dfrac{x^2−25}{2x+10}\).

    Suluhisho

    \(\begin{array} {ll} &R(x)=f(x)·g(x) \\ & \\ &R(x)=\dfrac{2x−6}{x^2−8x+15}·\dfrac{x^2−25}{2x+10} \\ & \\ \text{Factor each numerator and denominator.} &R(x)=\dfrac{2(x−3)}{(x−3)(x−5)}·\dfrac{(x−5)(x+5)}{2(x+5)} \\ & \\ \text{Multiply the numerators and denominators.} &R(x)=\dfrac{2(x−3)(x−5)(x+5)}{2(x−3)(x−5)(x+5)} \\ & \\ \text{Remove common factors.} &R(x)=\dfrac{\cancel{2}\cancel{(x−3)}\cancel{(x−5)}\cancel{(x+5)}}{\cancel{2}\cancel{(x−3)}\cancel{(x−5)}\cancel{(x+5)}} \\ & \\ \text{Simplify.} &R(x)=1 \end{array}\)

    Jaribu\(\PageIndex{32}\)

    Pata\(R(x)=f(x)·g(x)\) wapi\(f(x)=\dfrac{3x−21}{x^2−9x+14}\) na\(g(x)=\dfrac{2x^2−8}{3x+6}\).

    Jibu

    \(R(x)=2\)

    Jaribu\(\PageIndex{33}\)

    Pata\(R(x)=f(x)·g(x)\) wapi\(f(x)=\dfrac{x^2−x}{3x^2+27x−30}\) na\(g(x)=\dfrac{x^2−100}{x^2−10x}\).

    Jibu

    \(R(x)=\dfrac{1}{3}\)

    Ili kugawanya kazi za busara, tunagawanya maneno ya busara yanayosababisha upande wa kulia wa equation kwa kutumia mbinu sawa ambazo tulizitumia kugawanya maneno ya busara.

    MFANO\(\PageIndex{34}\)

    Pata\(R(x)=\dfrac{f(x)}{g(x)}\) wapi\(f(x)=\dfrac{3x^2}{x^2−4x}\) na\(g(x)=\dfrac{9x^2−45x}{x^2−7x+10}\).

    Suluhisho

    \(\begin{array} {ll} &R(x)=\dfrac{f(x)}{g(x)} \\ \text{Substitute in the functions }f(x),\space g(x). &R(x)=\dfrac{\dfrac{3x^2}{x^2−4x}}{\dfrac{9x^2−45x}{x^2−7x+10}} \\ & \\ \begin{array} {l} \text{Rewrite the division as the product of} \\ f(x)\text{ and the reciprocal of }g(x). \end{array} &R(x)=\dfrac{3x^2}{x^2−4x}·\dfrac{x^2−7x+10}{9x^2−45x} \\ & \\ \begin{array} {l} \text{Factor the numerators and denominators} \\ \text{and then multiply.} \end{array} &R(x)=\dfrac{3·x·x·(x−5)(x−2)}{x(x−4)·3·3·x·(x−5)} \\ & \\ \text{Simplify by dividing out common factors.} &R(x)=\dfrac{\cancel{3}·\cancel{x}·\cancel{x}\cancel{(x−5)}(x−2)}{\cancel{x}(x−4)·\cancel{3}·3·\cancel{x}\cancel{(x−5)}} \\ & \\ &R(x)=\dfrac{x−2}{3(x−4)} \end{array}\)

    Jaribu\(\PageIndex{35}\)

    Pata\(R(x)=\dfrac{f(x)}{g(x)}\) wapi\(f(x)=\dfrac{2x^2}{x^2−8x}\) na\(g(x)=\dfrac{8x^2+24x}{x^2+x−6}\).

    Jibu

    \(R(x)=\dfrac{x−2}{4(x−8)}\)

    Jaribu\(\PageIndex{36}\)

    Pata\(R(x)=\dfrac{f(x)}{g(x)}\) wapi\(f(x)=\dfrac{15x^2}{3x^2+33x}\) na\(g(x)=\dfrac{5x−5}{x^2+9x−22}\).

    Jibu

    \(R(x)=\dfrac{x(x−2)}{x−1}\)

    Dhana muhimu

    • Kuamua maadili ambayo kujieleza kwa busara haijulikani.
      1. Weka denominator sawa na sifuri.
      2. Kutatua equation.
    • Sawa Fractions Mali
      Kama\(a\)\(b\),, na\(c\) ni idadi ambapo\(b\neq 0\),\(c\neq 0\), basi

      \(\quad\dfrac{a}{b}=\dfrac{a·c}{b·c}\) na\(\dfrac{a·c}{b·c}=\dfrac{a}{b}.\)
    • Jinsi ya kurahisisha kujieleza kwa busara.
      1. Fanya namba na denominator kabisa.
      2. Kurahisisha kwa kugawa mambo ya kawaida.
    • Vikwazo katika kujieleza
      Mantiki
      kinyume cha\(a−b\) ni\(b−a\).

      \(\quad\dfrac{a−b}{b−a}=−1 \qquad a\neq b\)

      Maneno na mgawanyiko wake kinyume na\(−1\).
    • Kuongezeka kwa Maneno ya busara
      Ikiwa\(p\)\(q\),\(r\),, na\(s\) ni polynomials ambapo\(q\neq 0\)\(s\neq 0\), basi

      \(\quad\dfrac{p}{q}·\dfrac{r}{s}=\dfrac{pr}{qs}\)
    • Jinsi ya kuzidisha maneno ya busara.
      1. Factor kila nambari na denominator kabisa.
      2. Kuzidisha nambari na denominators.
      3. Kurahisisha kwa kugawa mambo ya kawaida.
    • Idara ya Maneno ya busara
      Ikiwa\(p\)\(q\),\(r\),, na\(s\) ni polynomials ambapo\(q\neq 0\)\(r\neq 0\),,\(s\neq 0\), basi

      \(\quad\dfrac{p}{q}÷\dfrac{r}{s}=\dfrac{p}{q}·\dfrac{s}{r}\)
    • Jinsi ya kugawanya maneno ya busara.
      1. Andika upya mgawanyiko kama bidhaa ya kujieleza kwa busara ya kwanza na usawa wa pili.
      2. Factor numerators na denominators kabisa.
      3. Kuzidisha nambari na denominators pamoja.
      4. Kurahisisha kwa kugawa mambo ya kawaida.
    • Jinsi ya kuamua uwanja wa kazi ya busara.
      1. Weka denominator sawa na sifuri.
      2. Kutatua equation.
      3. Kikoa ni namba zote halisi ukiondoa maadili yaliyopatikana katika Hatua ya 2.

    faharasa

    kujieleza kwa busara
    Maneno ya busara ni usemi wa fomu\(\dfrac{p}{q}\), wapi\(p\) na\(q\) ni polynomials na\(q\neq 0\).
    rahisi kujieleza busara
    Maneno rahisi ya busara hayana mambo ya kawaida, isipokuwa\(1\), katika nambari yake na denominator.
    kazi ya busara
    Kazi ya busara ni kazi ya fomu\(R(x)=\dfrac{p(x)}{q(x)}\) ambapo\(p(x)\) na\(q(x)\) ni kazi nyingi na\(q(x)\) sio sifuri.